• Bulletin of the Korean Mathematical Society
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• v.57 no.5
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• pp.1215-1229
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• 2020

Let D be an integral domain and S a multiplicative subset of D. An ascending chain (I_k)_k∈ℕ of ideals of D is said to be S-stationary if there exist a positive integer n and an s ∈ S such that for each k ≥ n, sI_k ⊆ I_n. As a generalization of domains satisfying ACCP (resp., ACC on ∗-ideals) we define D to satisfy S-ACCP (resp., S-ACC on ∗-ideals) if every ascending chain of principal ideals (resp., ∗-ideals) of D is S-stationary. One of main results of this paper is the Hilbert basis theorem for an integral domain satisfying S-ACCP. Also we investigate the class of such domains D and we generalize some known related results in the literature. Finally some illustrative examples regarding the introduced concepts are given.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.13 no.5
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• pp.1-8
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• 2013

This paper implements an integrated vehicle chassis system of ACC(Adaptive Cruise Control) and LKS(Lane Keeping System) based on OSEK OS to vehicle operating system and analyzes its performance through experiments. In recent years active safety and advanced driver assistance system has discussed to improve safety of vehicle. Among the rest, We integrate ACC that controls longitudinal velocity of vehicle and LKS that assists a vehicle in maintaing its driving lane, then implement integrated control system in vehicle. Implemented control system uses OSEK/VDX proposed standard, which is aiming at reusability and safety of software for vehicle and removal hardware dependence of application software. Redesigned control system based on OSEK OS, which is supported by OSEK/VDX, can manage real-time task, process interrupt and manage shared resource. We show by results performed EILS(ECU-In-the-Loop Simulation) that OSEK OS-based integrated controller of ACC and LKS is equivalent conventional integrated controller of ACC and LKS.

• Proceedings of the KIEE Conference
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• 2006.07c
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• pp.1564-1565
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• 2006

현재 전세계적으로 170kV급 이하의 초고압 지중케이블 접속함으로 기존의 현장몰드방식의 TMJ(Tape Molded Joint)와 부품조립방식의 PJ(Prefabricated Joint)보다 조립시간이 짧고 작업자의 숙련도가 높지 않아 경제적이며, 유지보수에 장점을 가진 고무몰드 접속함(PMJ)이 채용되고 있으며, 이러한 추세는 적용 전압급이 점차 상승하면서 230kV급까지 그 비중이 늘어나고 있는 경향을 보이고 있다. 당사에서는 이러한 추세에 발맞추어 154kV급 고무몰드접속함의 개발 당시의 Silicone의 기초물성시험 DATA 획득, 고무몰드 UNIT 및 금형 설계 기술 확립과 접속 공법 개발의 경험을 바탕으로 230kV급 고무몰드접속함의 개발에 성공하였다.

• ETRI Journal
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• v.40 no.3
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• pp.303-308
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• 2018

This paper proposes a simple yet accurate method for estimating the antenna correlation coefficient (ACC) of a high-order multiple-input multiple-output (MIMO) antenna. The conventional method employed to obtain the ACC from three-dimensional radiation patterns is costly and difficult to measure. An alternate method is to use the S-parameters, which can be easily measured using a network analyzer. However, this method assumes that the antennas are highly efficient, and it is therefore not suitable for lossy MIMO antenna arrays. To overcome this limitation, we define and utilize the non-coupled radiation efficiency in the S-parameter-based ACC formula. The accuracy of the proposed method is verified by the simulation results of a 4-port highly coupled lossy MIMO array. Further, the proposed method can be applied to N-port arrays by expanding the calculation matrix.

• Transactions of the Korean Society of Automotive Engineers
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• v.20 no.2
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• pp.103-109
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• 2012

Adaptive cruise control Stop&Go system has been developed to reduce the driver's workload on highway or public road. This system is characterized by a moderate control of engine and brake actuator. A control system capable of modeling driver's driving characteristics has been constructed to provide natural vehicle behavior in full speed driving. But, ACC Stop&Go system has some limitations. One of the limitations is a detection limitation on near cut-in situation. This paper presents development of the near cut-in test procedure, finding of the limitation value on near cut-in scenario and performance comparisons on ACC Stop&Go system.

• Proceedings of the KIEE Conference
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• 1994.07b
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• pp.1553-1555
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• 1994

In this paper, we describes the research in condenser cone of $SF_6$ gas sealing end for 345KV oil-filled cable. The designed of condenser cone based on the results electric field analysis by electrostatics theory ana FEM. As a results. we have been designed the condenser cone and the inner insulation part of $SF_6$ seating end, the width and length, the number of condenser, the length of stress relief slope, the total length of condenser cone.

• Journal of Auto-vehicle Safety Association
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• v.4 no.1
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• pp.5-11
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• 2012

This paper discusses the evaluation of the safety impact of the Adaptive Cruise Control (ACC) system in Korea. To evaluate the safety impact, this paper suggests an analysis method by using the test scenario and field operational test data. The test scenario is composed to represent the main component factor of the ACC system and ACC related accident situation such as rear-end collision, lane-change, and road-curvature, etc. Also, from the field operation test data, the system's potential to increase the safety can be measured ideally. Besides, field operational testdata was used to revise the expected safety impact value as Korean road conditions. By using the proposed evaluation method, enhanced safety impact of the ACC system can be estimated scientifically.

• Journal of Drive and Control
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• v.14 no.3
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• pp.8-17
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• 2017

With automobiles sharply increasing in numbers worldwide, we are faced with critical social issues such as traffic accidents, traffic jams, environmental pollution, and economic inefficiency. In response, research on ITS is promoted mainly by regions with advanced automotive industry such as the U.S., Europe, and Japan. While Korea is working on moving forward in the global market through developing and turning to global standards systems related to ASV (Advanced Safety Vehicle), the country is not fully prepared for such projects. The purpose of ACC (Adaptive Cruise Control) is to control a vehicle's longitudinal speed and distance and minimize driver workload. Such a system should be valuable in preventing accidents, as it reduces driver workload in the 21st-century world of telematics created by development of the automobile culture industry. In this light, the thesis presents a method to test and evaluate ACC system and a mathematical method to assess distance. For the proposed test and evaluation, theoretical values are tested with vehicle test and a database is acquired, by using vehicles equipped with an ACC system. Theoretical evaluation criteria for developing ACC system may be used and scenario-specific evaluation methods may find useful application through testing the formula proposed by comparing the database and mathematical method.

• Journal of the Korean Dietetic Association
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• v.19 no.3
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• pp.236-252
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• 2013

The purpose of this study was to assess the microbiological quality of home-delivered meals during production and delivery for children from low-income families. Production flows from a facility in Seoul that provides home-delivered meals were analyzed and the time-temperature of the food was measured. Microbiological assessment was performed for the production environment, personal hygiene, and food samples at each production and delivery step based on the process approach. It took 2 hours or longer from completion of production to meal delivery. An aerobic colony count (ACC) and coliform were not detected at knives, cutting boards, and dish towels. However, ACC (at pre-preparation, preparation, and packing areas) and coliform (at the preparation area) were detected on the hands and gloves of employees. Air-borne bacterial counts varied according to day and preparation area (ND~6 CFU/plate/15 min). Food temperatures, on the completion of production and meal delivery, fell into temperature danger zones. ACC and coliform counts of raw ingredients did not decrease after pre-preparation (washing and sanitizing) for menus involving food preparation with no cook step. ACC decreased after cooking step for menus of food preparation with cook step, but the ACC of the stir-fried and seasoned dried filefish fillet on the completion of cooking was too numerous to count due to improper heating. The ACC of seasoned young Chinese cabbages (a menu with complex food preparation) increased during delivery (from 2.5 log CFU/ml to 5.0 log CFU/ml). This qualitative assessment of foodborne pathogens revealed that B. cereus was detected in vegetable and meat product menus. These results suggest time-temperature control is necessary during production and delivery and management guidelines during production of home-delivered meals are provided for safe production.

• Transactions of the KSME C: Technology and Education
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• v.3 no.3
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• pp.201-207
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• 2015

Air cooled condenser for power plant is used at inland area of desert or mountainous area because condenser coolant like sea water is not necessary. However, the performance of air cooled condenser is influenced by ambient condition such as wind speed and air temperature. Therefore, various devices have been designed to improve the performance of air cooled condenser. In this study, the CFD analysis for air cooled condenser was carried out according to wind speed and wind screen configuration. As wind speed increased from 3m/s to 7m/s, the fan flow rate was reduced about 15.76% and the rise of inlet air temperature was 5.55 degree of Celsius. When the suitable wind screen is equipped, the fan flow rate went up about 5.18% and inlet air temperature dropped by 2.08 degree of Celsius in comparison with original case without wind screen at 7m/s wind speed.